Anthropogenic Specimen (Man Made Material)

Sandstone (Ferruginous)

Arenite (primarily SiO2 with Fe2O3/FeO(OH) cementing agents)

Petrified Wood

Silicified Wood (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Petrified Wood

Silicified Wood (SiO2)

Limestone

Calcium Carbonate (CaCO3)

Chert (Black Chert or Flint)

Silicon Dioxide (SiO2)

Chert (Flint)

Microcrystalline Quartz (SiO2)

Quartz with Iron Stains

Quartz (SiO2) with iron oxide/hydroxide staining

Serpentine

Serpentinite (rock) containing serpentine minerals (e.g., Antigorite, Lizardite, Chrysotile)

Granite

Granite (Phaneritic intrusive igneous rock)

Sandstone (Banded)

Clastic Sedimentary Rock (primarily Quartz, SiO2)

Granite

Phaneritic Felsic Igneous Rock (Granite)

Sandstone (Ferruginous)

Arenite (Fe-oxide cemented)

Red Siltstone

Siltstone (composed mainly of SiO2 and Fe2O3)

Granite

Phaneritic Igneous Rock (Granite)

Pink Granite

Phaneritic plutonic rock (dominated by Alkali Feldspar)

Ferruginous Quartzite (Red Sandstone/Quartzite)

Quartzite with Iron inclusions (SiO2 + Fe2O3)

Fluorite

Calcium Fluoride (CaF2)

Jasper

Jasper (Silicon Dioxide, SiO2)

Mica Schist

Mica Schist (KAl2(AlSi3O10)(OH)2 / K(Mg,Fe)3AlSi3O10(OH)2)

Granite

Granitic intrusive igneous rock

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Chert (Nodule)

Silicon Dioxide (SiO2)

Petrified Wood

Silicified Wood (SiO2)

Dinosaur Bone (Gembone)

Petrified Dinosaur Bone (Apatite/Silica replacement)

Red Sandstone (Iron-Rich)

Arenite (Fe2O3)

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Olivine (in Peridotite/Dunite form)

Magnesium Iron Silicate (Mg,Fe)2SiO4

Labradorite

Labradorite (Plagioclase Feldspar Series: (Ca,Na)(Al,Si)4O8)

Zebra Jasper

Tetragonal Silicon Dioxide (Quartz) with impurities

Petrified Wood

Silicified Wood (SiO2)

Caliche (also known as hardpan, calcrete, kankar)

Primarily composed of calcium carbonate (CaCO₃), often mixed with other minerals like quartz, clay minerals, and iron oxides.

Sandstone

Clastic sedimentary rock (primarily SiO2)

Fossil Coral (Petoskey Stone or Favosites)

Favosites (specifically Hexagonaria percarinata if silica-replaced Michigan type)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Sandstone (likely Arkosic)

Clastic Sedimentary Rock (Sandstone)

Amethyst

SiO2 (Silicon Dioxide) - Purple variety of Quartz

Chert (Pink Jasper/Agate variety)

Microcrystalline Quartz (SiO2)

Petrified Wood

Silicified Wood (SiO2)

Chert (specifically Flint or Novaculite variant)

Chert (Microcrystalline Quartz, SiO2)

Chert (Holey Stone)

Microcrystalline Quartz (SiO2)

Red Jasper

Jasper (Silicon Dioxide with Iron Oxide inclusions), SiO2